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71.
N-[1-Hydroxyimino-2-methyl-1-(2-pyridyl)prop-2-yl]hydroxylamine, a new representative of the series of α-hydroxylamino oximes,
was synthesized. Based on this compounds, 3-imidazoline 3-oxide and 2-imidazoline 3-oxide derivatives, were obtained, and
some of their chemical properties were investigated.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 131–136, January, 1997. 相似文献
72.
Chen Hui Li Hua Yu Qiu Cai Hong Xu 《中国化学快报》2007,18(12):1436-1438
Bis-silicon-bridged stilbene derivatives were synthesized in a modified procedure that combined the preparation of bis[2- (silyl)phenyl]acetylene and its intramolecular reductive cyclization in one pot.The results indicated that the one pot approach produced target products in a comparable yield to that of the two-step method reported previously. 相似文献
73.
RAHMAN Nafisur SINGH Manisha HODA Nasrul Md.ZAIDI S.M. Kashif R. BANU Naheed 《中国化学》2005,23(12):1611-1617
A simple sensitive and economical method for the determination of labetalol hydrochloride has been proposed, based on the reaction of labetalol with sodium nitroprusside and hydroxylamine hydrochloride in sodium dihydrogen phosphate-sodium hydroxide buffer solution of pH 12. The green-blue color produced due to the formation of a nitroso derivative has been measured at 695 nm. The Beer's range was obeyed in the concentration range of 2-51 μg·mL^-1 with molar absorptivity of 0.48 × 10^4 L·mol^-1·cm^-1. Rigorous statistical analyses were performed for the validation of the method. A detailed investigation of the selectivity of the method has been done to find it to be highly selective for the determination of labetalol hydrochloride in the presence of its acidic degradation product and common excipients of formulations. The proposed method was successfully applied to the determination of labetalol hydrochloride in the laboratory prepared dosage forms. Comparison of the means of the proposed procedure with a reference method using point as well as interval hypotheses showed no statistically significant difference. The developed method was extended to investigate its applicability to biological samples. 相似文献
74.
Huong Doan Thi Mai Thang Pham Toan Giap Tran Huu Vu Thi Kim Oanh Nguyen Thi Minh Hang 《Natural product research》2020,34(19):2772-2778
AbstractTwo new prenylated flavonoids, 4´-methyl-8-prenyltaxifolin (1) and 6,8-diprenyl-4´-methyl-naringenin (2) and a new geranylated stilbene, 4′-deprenyl-4-methoxymappain (3) together with eight known flavonoids (4–11) were isolated from the fruits of Macaranga balansae Gagnep. Their chemical structures were determined by means of spectroscopic methods including 1D, 2D NMR, and MS data. Compound 2 showed the highest cytotoxic activity against PanC1, A549, KB and LU-1 cell lines with IC50 values range from 7.89 to 22.81?µM. 相似文献
75.
A wide variety of aldehydes were efficiently converted to their corresponding carboxylic acids in high yields using H2O2/HCl in the presence of hydroxylamine hydrochloride. In addition, selective oxidation of aldehydes in the presence of other functional groups such as hydroxyl group, carbon‐carbon double bond and other heteroatoms can be considered a noteworthy advantage of this method. 相似文献
76.
In this paper new heterocyclic compounds 5-[(1,1-dimethyl)ethyl]-3-aryl-(1H-l,2,3-triazol-1-yl)-5-isoxazolodinols were obtained by the reaction of vinyl triazole derivatives with hydroxylamine hydrochloride under the action of sodium carbonate. The biological tests indicate that they had plant-growth regulating activity. 相似文献
77.
无膦钯催化Heck反应合成新型芳维A酸类化合物 总被引:1,自引:0,他引:1
考察了以二环己基胺作配体的无膦钯催化Heck反应条件, 建立起一种新型的无膦钯催化Heck反应体系. 应用该体系可高收率(72%~84%)、高立体选择性(83%~95%)合成二取代和三取代二苯烯类化合物. 以2,4,5-三甲氧基苯乙烯、α-细辛脑为原料, 合成了4个尚未见文献报道的新型二苯烯类芳维A酸甲酯(3a, 3b, 4a, 4b), 并且在温和的水解体系[LiOH, V(THF)∶V(H2O)=5∶1]下顺利得到了它们的水解产物芳维A酸(5a, 5b, 6a, 6b), 产物通过1H NMR, 13C NMR, IR和MS进行了结构确认. 相似文献
78.
79.
Stephanie E. Martinez Casey L. Sayre Neal M. Davies 《Biomedical chromatography : BMC》2013,27(1):67-72
A method of analysis for 3‐methoxypterostilbene [trans‐3,3′5‐trimethoxy‐4′hydroxystilbene] in biological fluids is necessary to study pharmacokinetics. A novel and simple high‐performance liquid chromatographic method was developed for the determination of 3‐methoxypterostilbene in rat serum and urine. The internal standard, pinosylvin, was added to 0.1 mL serum or urine (serum proteins were precipitated with cold acetonitrile at ?20°C). Separation was achieved with a Phenomenex® C18 (2) (5 µm, 250 × 4.60 mm) column with ultraviolet detection at 327 nm. The calibration curves in both matrices were linear ranging from 0.05 to 100 µg/mL, and the mean extraction efficiency was >99%. Precision of the assay for both matrices was <12% (RSD) and was within 13% for all points on the calibration curve. The limit of quantification for this method was 0.05 µg/mL. The assay was successfully applied to a preliminary study of 3‐methoxypterostilbene pharmacokinetics in a rat. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
80.
Denis Hervé Seuyep Ntoukam Gerrit Albert Luinstra Patrick Theato 《Journal of polymer science. Part A, Polymer chemistry》2014,52(19):2841-2849
A new 1,1‐disubstituted‐2‐vinylcyclopropane monomer bearing a ketone and a pentafluorophenyl ester was synthesized and successfully polymerized to yield a polymer with two side chain moieties readily available for post‐polymerization modification. After a quantitative modification of the pentafluorophenyl moiety with amines, a subsequent second functionalization reaction was successfully performed on the ketone moiety leading to a double side‐chain functionalized polymer using two different routes. The first route utilized hydrazide and hydroxylamine derivatives leading to a ketone conversion of 25 to 85%. In the second route, the ketone moiety was first reduced to alcohol (reduction conversion up to 100%) and then converted into the corresponding ester or urethane using acyl halides or isocyanates, respectively, with a conversion ratio of up to 90%. A library of functionalized polymers was synthesized to confirm the effectiveness of this approach. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014 , 52, 2841–2849 相似文献